Extended vote-counting, protracted litigation, and President Trump’s reluctance to concede the 2020 presidential election have held the Republican Party back from the usual work of losers in a national election, which is self-examination.

Part of this may be the result of the better-than-expected showing of Republicans in races for Congress and state legislatures. Part of it may be a desire to wait for January, when the outcome of the Georgia runoffs will determine control of the Senate. Republicans are unsure whether to pat themselves on the back for holding on to Congress or flagellate themselves for failing to hold the White House.

Some of the most important factors in the outcome of the election were outside of Trump’s control. The Democrats selected a candidate who, in Joe Biden, was difficult to caricature as a socialist radical, because he had just vanquished Bernie Sanders and Elizabeth Warren in a contested campaign for the nomination. The election was disrupted, and the economy slowed, by a global pandemic.

At some point though, Republicans will have to take a clear-eyed look not only at the presidential campaign but at the Trump presidency and see how they might have done better. That doesn’t mean replaying the 2016 primary and concluding that the party would have been better off running Jeb Bush or Ted Cruz or Marco Rubio against Hillary Clinton, and that the entire Trump adventure was an erroneous digression, though some will surely make that case. But it does mean being like a football team watching the video carefully the day after the game, trying to learn from the mistakes and improve.

Race and sex. Republicans do pretty well with white male voters. They do less well with women and Blacks. There were lots of minority and women faces on display at the Republican National Convention, but there were fewer in top positions in the Trump administration. Trump-Pence 2016 might have been the last all-white-male winning presidential and vice-presidential ticket that American voters see in a long time.

Immigration. Americans want to think of themselves as kind, not cruel. Separating parents from children at the border was an issue that marked Mr. Trump as cruel and cost him support from Catholic bishops. Mr. Trump offered mixed messages on the immigration issue, showcasing a naturalization ceremony at the Republican National Convention but also dwelling on the border wall.

One might argue that Mr. Trump was consistent in distinguishing between legal and illegal immigration, but the party overall seems hesitant to repudiate its factions that insist even legal immigration drives down wages or somehow weakens American culture. Mr. Trump repeatedly denounced “chain migration,” and he reduced legal refugee admission levels.

Republicans can expect every one of their candidates to be demonized by Democrats as racist and sexist. There are plenty of substantive economic reasons to favor increased immigration as pro-growth. There’s also the political reason that a pro-immigration policy will undercut the racism accusation. Not for nothing did Ronald Reagan kick off his 1980 general election campaign with a Statue of Liberty and Ellis Island backdrop: “These families came here to work… We all came from different lands but we share the same values, the same dream.”

Foreign Policy. Mr. Trump spent substantial time and energy pursuing a nuclear disarmament deal with North Korea that was never consummated. He talked tough on China but offered enough mixed signals that Vice President Biden ran arguing that he’d be tougher on China than Mr. Trump.

In the Middle East, where Trump saw some of his greatest diplomatic successes, the president waited until 2020 to roll out a peace plan. On Iran, the president undercut his achievement of leaving the Iran nuclear deal by promising to ink another Iran deal rapidly if re-elected. Mr. Trump’s understandable desire to bring American GIs home nevertheless sometimes left an impression of disorderly retreat.

Markets and capitalism. While depicting Mr. Biden and the Democrats as socialists, Mr. Trump campaigned against “Big Pharma” and Big Tech, announced limits on offshore oil drilling, and even denounced military contractors. It muddied the message that a regulatory rollback had boosted the economy.

Taxes. Mr. Trump ran for re-election on a vague promise of additional tax-cutting, but his corporate tax cuts were paid for in part by a capping of the individual deduction for state and local taxes. That rubbed “SALT” in the wounds of voters in such places as the high-property-tax suburbs of Philadelphia, suburban Atlanta, Arizona.

Politics as entertainment. The reality-show drama has always been part of Mr. Trump’s persona. Eventually, though, the personnel churn and the constant crisis atmosphere, to which the press contributed, led to a kind of fatigue that made Mr. Biden’s dullness seem attractive by comparison.

Perhaps a second-term Trump would have learned from his mistakes. More likely, he would have seen a victory as validation. His insistence that he somehow really won risks delaying a reckoning with the reasons he lost.